3D-display systems have existed in a variety of forms for many years. Generally, these systems convey a sense of depth by presenting slightly different views of a similar image to each of a viewer's eyes. One typical 3D-display system involves presenting two superimposed images simultaneously from a single display screen with each image modified in such a way that a specially designed light-filter may cancel out one image or the other. By placing a different filter in front of each of a viewer's eyes, the viewer may see one image in their left eye and a different image in their right eye when looking at the same display. If the two images are slightly offset views of the same scene, the viewer will instinctively combine the images into a 3D representation of the scene. Conventional systems have employed color filters (such as the red/cyan glasses), type of light-polarization (i.e., planar, elliptical, linear, etc.), or polarization angle as characteristics for filtering images using filters placed near to the eyes.
More recently, displays have been developed that can present 3D images without placing filters near the eyes. Such systems, known as autostereoscopic displays, hold tremendous potential for bringing 3D-display technology to a variety of untapped applications. Emerging uses for 3D technology include medical imaging, entertainment, diagnostics, education, and defense, among many other fields.